CN102081333A

CN102081333A - Fixing device

Info

Publication number: CN102081333A
Application number: CN2010105724478A
Authority: CN
Inventors: 石田圭; 藤原靖史; 铃木登; 宫内义弘; 近藤知广
Original assignee: Brother Industries Ltd
Current assignee: Brother Industries Ltd
Priority date: 2009-11-30
Filing date: 2010-11-30
Publication date: 2011-06-01
Anticipated expiration: 2030-11-30
Also published as: EP2330466B1; JP2011113013A; US20110164906A1; CN102081333B; US20130287459A1; JP5263131B2; EP2330466A1; US8494424B2; US9274472B2

Abstract

A fixing device for thermally fixing a developer image to a sheet fed in a sheet feeding direction includes: a tubular flexible fixing member; a nip plate; a heater: a reflection plate; a supporting member; a temperature sensor. The tubular flexible fixing member has an inner peripheral surface defining an inner space. The crimping plate is disposed in the inner space and has one surface and an opposite surface. The inner peripheral surface is in sliding contact with one surface. The heater is disposed in the inner space and faces the crimping plate along the facing direction. The reflective plate reflects radiant heat from the heater toward the crimping plate. The support member cooperates with the nip plate to provide a nip area for pinching the fixing member between the support member and the nip plate. The temperature sensor is arranged in the inner space, and detects the temperature of the clamping plate. The temperature sensor is located on the outer side of the reflection plate in the sheet feeding direction and faces the opposite surface. The fixing device can detect the temperature of the nip plate with high accuracy while suppressing damage and wear of the temperature sensor and the fixing belt.

Description

Fixing device

Technical field

The present invention relates to a kind of will be through the developer thermal image photographic fixing of transfer printing fixing device to sheet material.

Background technology

Disclosed Japanese Patent Application No.2006-251479 discloses a kind of heat-fixing device that is used for electro photography type image device.The well heater that described fixing device comprises the photographic fixing band, be placed at the place, space that limits in the interior perimeter surface of photographic fixing band is Halogen lamp LED, cramping plate and pressure roll for example.Between cramping plate and pressure roll, define the cramping zone by the photographic fixing band.Thereby be provided with temperature sensor is used to control fixing temperature with detected temperatures control well heater.More specifically, form recess in the surface of the cramping plate of sliding contact with it at the photographic fixing band, and temperature sensor for example the contact-type thermal resistor be arranged in this recess.

Summary of the invention

Be in the JP communique in the disclosed fixing device, because temperature sensor contacts with the cramping plate, so can carry out with pin-point accuracy for the temperature detection of cramping plate.Yet, because the edge of opening sliding contact of the interior perimeter surface of photographic fixing band and temperature sensor and recess during the circular motion of photographic fixing band, so the interior perimeter surface and the temperature sensor of photographic fixing band can be damaged or wear and tear, thereby have reduced its serviceable life.In view of aforementioned, the object of the present invention is to provide a kind of fixing device, described fixing device can detect the temperature of cramping plate with pin-point accuracy in the damage and wear that suppresses temperature sensor and photographic fixing band.

In order to realize above and other purpose, the invention provides a kind of fixing device, described fixing device is used for the photographic fixing of developer thermal image to along the sheet material of sheet feeding direction feeding, and described fixing device comprises: the flexible fixing member of tubulose; The cramping plate; Well heater; Reflecting plate; Support unit; And temperature sensor.The flexible fixing member of described tubulose has the interior perimeter surface that limits the inner space.Described cramping plate is arranged in the described inner space, and has a surface and opposed surface.A perimeter surface and a described surperficial sliding contact in described.Described well heater is arranged in the described inner space, and faces described cramping plate along faces direction.Described reflecting plate from well heater towards cramping plate reflected radiation heat.Described support unit matches with the cramping plate cramping zone is provided, and is used for the flexible fixing member of the described tubulose of cramping between support unit and cramping plate.Described temperature sensor is arranged in the described inner space, and detects the temperature of cramping plate.Described temperature sensor be positioned at reflecting plate along the outside of sheet feeding direction and in the face of described opposed surface.

The flexible fixing member of preferably described tubulose is the photographic fixing film.

Preferably described temperature sensor directly contacts with described opposed surface.

Preferably described temperature sensor and described opposed surface be restriceted envelope between described temperature sensor and described opposed surface.

Preferably described temperature sensor is positioned at the outside along described sheet feeding direction in described cramping zone.

Preferably described temperature sensor is positioned at the downstream along described sheet feeding direction of described reflecting plate.

Preferably described temperature sensor is positioned at the upstream along described sheet feeding direction of described reflecting plate.

Preferably described cramping plate has along the outstanding outshot of sheet feeding direction, and described temperature sensor is in the face of described outshot location.

Preferably described cramping plate have along with the outstanding in the opposite direction outshot in sheet feeding side, described temperature sensor is in the face of described outshot location.

Preferably described temperature sensor and described reflecting plate limit the gap between described temperature sensor and described reflecting plate.

Preferably described fixing device further comprises pillar, described pillar covers described reflecting plate and supports described cramping plate, described pillar has the profile that conforms to the exterior contour of reflecting plate, and described pillar is formed with one in through hole and the recess, and described temperature sensor extends through described in described through hole and the recess.

Description of drawings

In the drawings:

Fig. 1 is the schematic cross-sectional view that the structure of the laser printer with fixing device according to an embodiment of the invention is shown;

Fig. 2 is the schematic cross-sectional view according to the fixing device of this embodiment;

Fig. 3 is the skeleton view according to the fixing device of this embodiment;

Fig. 4 is the decomposition diagram that Halogen lamp LED, cramping plate, reflecting plate, pillar, thermal resistor and thermostat are shown;

Fig. 5 is the schematic cross-sectional view according to the fixing device of first modification of the present invention;

Fig. 6 A is the schematic cross-sectional view according to the fixing device of second modification of the present invention;

Fig. 6 B is the schematic cross-sectional view according to the fixing device of the 3rd modification of the present invention; And

Fig. 7 is the schematic cross-sectional view according to the fixing device of the 4th modification of the present invention.

Embodiment

Below, the general structure as the laser printer of imaging device according to an embodiment of the invention will be described with reference to figure 1 time.Laser printer 1 shown in Figure 1 is provided with the fixing device 100 according to the embodiment of the invention.With afterwards with reference to figs. 2 to the detailed structure of describing fixing device 100 at 7 o'clock.

The general structure of＜laser printer 〉

As shown in FIG. 1, laser printer 1 comprises the main frame 2 that has removable protecgulum 21.Be provided with in main frame 2: be used to supply the sheet material feeding unit 3 of sheet material P, exposing unit 4 is used for that toner image (developer image) is transferred to the handle box 5 on the sheet material P and is used for the fixing device 100 of the hot photographic fixing of toner image to the sheet material P.

Instructions in full in, will be when hypothesis uses the orientation of laser printer to place laser printer 1 with expection, use term " on ", D score, " left side ", " right side ", " preceding ", " back " etc.In use, place laser printer 1 as shown in Figure 1.More specifically, in Fig. 1, left side and right side are respectively rear side and front side.

Sheet material feeding unit 3 is arranged at the place, bottom of main frame 2.Sheet material feeding unit 3 comprises: is used to hold the sheet material supplies trays 31 of sheet material P, is used to upgrade the riser 32 of the front side of sheet material P, and sheet material feed rolls 33, sheet material supply pad 34, paper dirt is removed roller 35,36 and alignment rolls 37.Each that hold in sheet material supplies trays 31 is opened a sheet material P and is raised plate 32 and upwards is directed to sheet material feed rolls 33, is separated by sheet material feed rolls 33 and sheet material supply pad 34, and removes roller 35,36 and alignment rolls 37 by towards handle box 5 transmission through paper dirt.

Exposing unit 4 is arranged at the place, top of main frame 2.Exposing unit 4 comprises: laser emission element (not shown), polygon mirror 41, lens 42,43 and catoptron 44,45,46.In exposing unit 4, laser emission element is suitable for based on view data projecting laser bundle (utilizing dotted line to represent in Fig. 1), so that laser beam is with polygon mirror 41, lens 42, catoptron 44,45, the order of lens 43 and catoptron 46 is by described polygon mirror 41, lens 42, catoptron 44,45, lens 43 and catoptron 46 deflections or process.The high-velocity scanning of laser beam is stood on the surface of photosensitive cylinder 61.

Handle box 5 is arranged at below the exposing unit 4.By the open front that limits by protecgulum 21 in open position, can separate or connect handle box 5 with respect to main frame 2.Handle box 5 comprises roller unit 6 and developing cell 7.

Roller unit 6 comprises photosensitive cylinder 61, charged device 62 and transfer roll 63.Developing cell 7 is installed to roller unit 6 with detachable way.Developing cell 7 comprises developer roll 71, toner feed rolls 72, adjustment blade 73 and holds the toner accommodating part 74 of toner (developer) therein.

In handle box 5, after charged device 62 uniform chargeds had been passed through in the surface of photosensitive cylinder 61, the high-velocity scanning from the laser beam of exposing unit 4 was stood on described surface.On the surface of photosensitive cylinder 61, form electrostatic latent image thus based on view data.The toner that holds in toner accommodating part 74 is fed to developer roll 71 via toner feed rolls 72.Toner is at developer roll 71 and adjust between the sword 73 and be transmitted, with as veneer with uniform thickness on developer roll 71.

The toner that is deposited on the developer roll 71 is supplied to the electrostatic latent image that forms on photosensitive cylinder 61.Therefore, on photosensitive cylinder 61, form visual toner image corresponding to electrostatic latent image.Then, sheet material P is transmitted between photosensitive cylinder 61 and transfer roll 63, so that the toner image that forms on photosensitive cylinder 61 is transferred on the sheet material P.

Fixing device 100 is arranged on handle box 5 back.When sheet material P process fixing device 100, be transferred to toner image (toner) the hot photographic fixing on sheet material P on the sheet material P.Thereby toner image is transmitted roller 23 and 24 by the sheet material P of hot photographic fixing and transmits discharge on discharging pallet 22 thereon.

The detailed structure of＜fixing device 〉

As shown in Fig. 2 and Fig. 3, fixing device 100 comprises: the flexible tubular fixing member is pipe or film 110 for example, Halogen lamp LED 120 as well heater, cramping plate 130, reflecting plate 140 as reflection part, as the pressure roll 150 of support unit, pillar 160 is as two thermal resistors 170 and the thermostat 180 of temperature sensor.

In the following description, forward/backward direction will abbreviate " sheet feeding direction " as, and horizontal direction or to the right/left direction will abbreviate sheet material P " Width " as.

Photographic fixing film 110 is for having thermal resistivity and flexible tubular configuration.Each width end of tubular film 110 is by the guide member (not shown) guiding of the shell (not shown) that is fixed to fixing device 100, so that photographic fixing film 110 can move with circular movement pattern.

Halogen lamp LED 120 is well heaters of heating cramping plate 130, is used to heat the photographic fixing film 110 of the toner on the sheet material P with heating.Halogen lamp LED 120 is positioned at the place, inner space of photographic fixing film 110, and spaced apart with the inside surface of preset distance and cramping plate 130.

Cramping plate 130 is suitable for receiving pressure from pressure roll 150, and is adapted to pass through photographic fixing film 110 radiation heat is delivered to toner on the sheet material P from Halogen lamp LED 120.For reaching this purpose, cramping plate 130 is located in a fixed manner, makes the interior perimeter surface of photographic fixing film 110 slidably move by the lower surface of grease for cramping plate 130.

Cramping plate 130 by the material with the temperature conductivity that is higher than the pillar 160 that is formed from steel (describing afterwards) for example aluminium make.Cramping plate 130 has foundation 131 and two outshots 132.

Foundation 131 has central part 131A and end, front and back 131B along the sheet feeding direction.Central part 131A is outstanding towards pressure roll 150, and has and scribble black or be provided with the heat absorption parts with efficiently from the inside surface of Halogen lamp LED 120 absorbed radiation heat.

Rearward end 131B has back edge 131R, and two outshots 132 are outstanding backward along the sheet feeding direction from back edge 131R.As shown in FIG. 4, outshot 132 lays respectively at right part and the central part place along Width.

As shown in FIG. 4, cramping plate 130 has: be provided with smooth extension insertion portion 131C the right part and be provided with the left part at junction surface 134.When observing from the left side, junction surface 134 has the U-shaped structure, comprises upwardly extending sidewall sections 134A and is formed with conjugate foramen 134B.

Reflecting plate 140 is suitable for towards the radiation heat of cramping plate 130 (towards the inside surface of foundation 131) reflection from Halogen lamp LED 120 radiation.As shown in FIG. 2, reflecting plate 140 is positioned at photographic fixing film 110, and centers on Halogen lamp LED 120 in the mode with Halogen lamp LED 120 spaced apart preset distances.Therefore, can be focused on efficiently on the cramping plate 130 from the heat of Halogen lamp LED 120, with rapid heating cramping plate 130 and photographic fixing film 110.

Reflecting plate 140 is configured to have the U-shaped cross section, and by the material that has high reflectance for infrared-ray and far ir ray for example aluminium make.Reflecting plate 140 has U-shaped reflecting part 141 and bead part 142, and bead part 142 each end of 141 is extended along the sheet feeding direction from the reflecting part.In order to strengthen the reflect heat rate, can on the surface of aluminium reflecting plate 140, carry out minute surface finishing to realize direct reflection.

As shown in FIG. 4, at each width end place of reflecting plate 140 two junction surfaces 143 are set.Each junction surface 143 is located highlyer than bead part 142.Form two recesses 144 in position corresponding to outshot 132.

Pressure roll 150 is positioned at below the cramping plate 130, and the cramping photographic fixing film 110 that matches with cramping plate 130, to be provided for the cramping zone N of cramping sheet material P between pressure roll 150 and photographic fixing film 110.In other words, pressure roll 150 is used for providing cramping zone N by photographic fixing film 110 crushing clamp pressing plates 130 between pressure roll 150 and photographic fixing film 110.

Pressure roll 150 drives with rotation mode by the CD-ROM drive motor (not shown) of being located in the main frame 2.By the rotation of pressure roll 150 because at photographic fixing film 110 along the friction force that produces between the cramping plate 130 or between sheet material P and photographic fixing film 110, photographic fixing film 110 moves with circular movement pattern along cramping plate 130.The toner image on the sheet material P can utilize sheet material during N place in the cramping between pressure roll 150 and the photographic fixing film 110 zone is passed through heat and pressure and by hot photographic fixing in sheet material.

Pillar 160 is suitable for the end 131B of propclip pressing plate 130, is used to keep the rigidity of cramping plate 130.Pillar 160 has the U-shaped structure, has antetheca 160F, the rear wall 160R and the roof 160T that conform to the profile of the reflecting part 141 that covers reflecting plate 140.In order to make pillar 160, high degree of rigidity parts for example steel plate are folded into U-shaped to have antetheca 160F, rear wall 160R and roof 160T.

As shown in FIG. 4, each among antetheca 160F and the rear wall 160R all has bottom 163.

Owing to assemble cramping plate 130 with reflecting plate 140 and pillar 160, the bottom 163 of antetheca 160F and rear wall 160R by cramping between junction surface, the left and right sides 143.Just, right junction surface 143 contacts with end, bottom right 163, and left junction surface 143 contacts with end, lower-left 163.As a result, joint that can be by between junction surface 143 and bottom 163, constraint reflecting plate 140 is because the vibration that the operation of fixing device 100 causes and being shifted along Width.

Antetheca 160F and rear wall 160R have the right part that is provided with L shaped engagement leg 165, and each L shaped engagement leg 165 is all extended left downwards then.The insertion portion 131C of cramping plate 130 can be inserted in the space between the engagement leg of facing 165 and 165.In addition, because described insertion, each end 131B of foundation 131 can abut against on each engagement leg 165.

Roof 160T has the left part that is provided with retainer 167, and retainer 167 has the U-shaped structure.Retainer 167 has a pair of maintenance wall 167A, keeps the inside surface of wall 167A to be provided with copulational protuberance 167B, and each copulational protuberance can engage with each conjugate foramen 134B.

As shown in Fig. 2 and Fig. 4, each Width end of among antetheca 160F and the rear wall 160R each has the inside surface that is provided with two abutment lugs 168, abutment lug 168 inwardly outstanding with reflecting part 141 front side walls and rear wall along sheet feeding direction adjacency.Therefore, because reflecting part 141 abutment lugs 168 can retrain reflecting plate 140 because the operation of fixing device causes 100 vibration and is shifted along the sheet feeding direction.

Between the outside surface of the inside surface of pillar 160 and reflecting plate 140, limit thin layer gap S.Gap S can suppress may be owing to cool exterior air flows into the thermal loss that takes place.In addition, the air among the S of gap is difficult for flowing to the outside, makes air to keep layer as heat when heating, and this heat keeps layer to prevent that heat is discharged into the outside from reflecting plate 140.Therefore, can be improved with rapid heating cramping plate 130 for the efficient of cramping plate 130 heating.

As shown in Fig. 3 and Fig. 4, the rear wall 160R of pillar 160 is formed with two recesses 161 that are used at two thermal resistors of aiming at two outshots 132 170 in location, position.In addition, each recess 161 is sized to provides and the minim gap of thermal resistor 170 (contacting with thermal resistor 170 avoiding).

Use traditional temperature sensor thermal resistor 170 as the temperature that is used to detect cramping plate 130.More specifically, as as shown in Fig. 2 and Fig. 3, two thermal resistors 170 are positioned at the space that the perimeter surface by photographic fixing film 110 limits, each thermal resistor 170 has to be provided with and utilizes screw 179 to be fixed to the top of the fixedly rib 173 of rear wall 160R, and have with the upper surface of outshot 132 over against lower surface.Upper surface be with the surface of the surface opposite of photographic fixing film 110 sliding contacts.Lower surface is as the temperature detection surface 171 that contacts with the upper surface of outshot 132.Each recess 144 prevents that the thermal resistor 170 on the outshot 132 from directly placing on the bead part 142.

In addition, as shown in FIG. 2, each thermal resistor 170 is positioned at the outside along the sheet feeding direction of the reflecting part 141 of reflecting plate 140.More specifically, each thermal resistor 170 be positioned at cramping zone N along the outside of sheet feeding direction and the downstream along the sheet feeding direction of reflecting plate 140 (rear side).In addition, each thermal resistor 170 and the outside surface of reflecting part 141 are spaced apart directly contacts with it avoiding.

The control module (not shown) is located in the main frame 2, and each thermal resistor 170 is connected to control module, is used for detection signal is transferred to control module.Therefore, can by the output of control Halogen lamp LED 120, perhaps, be controlled at the fixing temperature at N place, cramping zone based on the signal of the detected temperature of indication by carry out ON/OFF control for Halogen lamp LED 120.In the art, this control is well-known.

Traditional detector unit for example bimetallic devices can be used as the thermostat 180 of the temperature that is used for detection of reflected plate 140.More specifically, thermostat 180 is positioned at the space that the perimeter surface by photographic fixing film 110 limits, and each Width end of thermostat 180 is provided with and utilizes screw 189 to be fixed to the fixture 183 of the roof 160T of pillar 160 as shown in FIG. 3, makes thermostat 180 be positioned at reflecting plate 140 tops.Thermostat 180 have as with reflecting plate 140 over against the lower surface on temperature detection surface 181.In other words, with respect to reflecting plate 140, thermostat 180 and Halogen lamp LED 120 relative positionings.

Here, reflecting plate 140 presents temperature in the mode that is similar to cramping plate 130 and rises, and this is because reflecting plate 140 is similar to cramping plate 130 directly from Halogen lamp LED 120 received radiation heat.In the present embodiment, be substantially equal to distance between the top of Halogen lamp LED 120 and reflecting plate 140 in the distance between the central part 131A of Halogen lamp LED 120 and cramping plate 130.Correspondingly, the temperature ascendant trend of reflecting plate 140 is similar to the temperature ascendant trend of cramping plate 130.Therefore, can detect the state of Halogen lamp LED 120 by the temperature of utilizing thermostat 180 detection of reflected plates 140, that is, and the temperature of Halogen lamp LED 120.

Thermostat 180 is located in the power circuit of Halogen lamp LED 120 power supply, and is suitable for cutting off when the temperature that detects above predetermined temperature the power supply to Halogen lamp LED 120.Therefore, can prevent to rise in the excess temperature at fixing device 100 places.

Incidentally, because reflecting plate 140 is to be used for radiation heat is reflexed to the parts of cramping plate 130 from Halogen lamp LED 120,, the fast temperature of reflecting plate 140 self do not take place so rising.Therefore, originate in to moment that Halogen lamp LED 120 is powered, the temperature that ends at cramping zone N become predetermined rising temperature the moment time cycle and originate in that to become between time cycle in the moment of predetermined rising temperature time of origin to moment that Halogen lamp LED 120 is powered, the temperature that ends at reflecting plate 140 poor.In order to compensate this mistiming, should select to present the specific thermostat 180 of optimum temperature sensing range, perhaps should on temperature detection surface 181, apply black so that temperature absorption.

When reflecting plate 140 and cramping plate 130 are assembled into the pillar 160 of stationary heat sensitive resistor 170 and thermostat 180, at first, at abutment lug 168 reflecting plate 140 temporarily is assembled into pillar 160 by the abut outer surfaces that makes reflecting part 141.In this case, junction surface 143 contacts with bottom 163.

Then, as shown in FIG. 3, insertion section 131C is inserted between the

engagement leg

165 and 165, engage so that foundation 131 can form with engagement leg 165.After this, copulational protuberance 167B is engaged with conjugate foramen 134B.By this joint, each bead part 142 all is sandwiched between cramping plate 130 and the pillar 160.Therefore, make cramping plate 130 and reflecting plate 140 remain to pillar 160.

Each bead part 142 of reflecting plate 140 is sandwiched between each end 131B of pillar 160 and cramping plate 130.Therefore, the vertical displacement that the vibration that reflecting plate 140 causes owing to the operation of fixing device 100 takes place can access constraint, with the position with respect to cramping plate 130 fixation reflex plates 140, and keeps the rigidity of reflecting plate 140.

Incidentally, the pillar 160 of retaining clip pressing plate 130 and reflecting plate 140 and Halogen lamp LED 120 are held the guide member (not shown) of the circular motion of guiding photographic fixing film 110.Guide member is fixed to the main casing (not shown) of fixing device 100.Therefore, photographic fixing film 110, Halogen lamp LED 120, cramping plate 130, reflecting plate 140 and pillar 160 are held the main casing of fixing device 100.

Fixing device 100 according to the foregoing description provides following advantage and effect: because during the circular motion of photographic fixing film 110, the direct friction contact does not take place between photographic fixing film 110 and thermal resistor 170, so for example swipe and wear and tear and can be inhibited for any damage of photographic fixing film 110 and thermal resistor 170.This is due to the fact that thermal resistor 170 is positioned on the upper surface of cramping plate 130, and described upper surface and photographic fixing film 110 be the surface opposite of sliding contact with it.

Because thermal resistor 170 is positioned at the outside along the sheet feeding direction of reflecting plate 140, so thermal resistor 170 directly is not subjected to the photothermal influence from Halogen lamp LED 120.Therefore, thermal resistor 170 can accurately detect the temperature of cramping plate 130, to strengthen temperature controlled accuracy.

In addition, because thermal resistor 170 is positioned at the outside of reflecting plate 140, so need in thermal resistor 170, not improve thermal resistivity to reduce production cost.If thermal resistor is positioned at the inside of reflecting plate 140, then this thermal resistor requires high thermal resistivity.

Because thermal resistor 170 is positioned at the outside of reflecting plate 140, can be concentrated on efficiently on the cramping plate 130 from the radiation heat of Halogen lamp LED 120 and reflecting plate 140 and do not interrupted by thermal resistor 170.Therefore, can carry out Fast Heating, to quicken the startup timing of fixing device 100 for cramping plate 130.

Particularly, because thermal resistor 170 is positioned at the N outside, cramping zone, so this radiation heat can be focused on the central part 131A of cramping plate 130.Therefore, the temperature of cramping zone N rises and can stablize and generation equably, improves hot photographic fixing operation thus.

Because thermal resistor 170 is positioned at the downstream along the sheet feeding direction of reflecting plate 140, so can utilize the inner space of photographic fixing film 110 efficiently.More specifically, the part of photographic fixing film 110 that is right after the upstream of cramping zone N is subjected to tension force, and because the rotation of pressure roll 150, and the part that is right after at the photographic fixing film 110 in the downstream of cramping zone N relaxes.Therefore, because described lax, can provide sufficient inner space at the place, downstream of reflecting plate 140.Therefore, thermal resistor 170 can be positioned at lax spatial portion office.

In addition, because do not need to be used to install any particular space of thermal resistor 170, so the inner space of photographic fixing film 110 can be the compact circumferential lengths with minimizing photographic fixing film 110.Correspondingly, the circumference moving period that can reduce photographic fixing film 110 quickens the startup timing of fixing device 100 thus to suppress from photographic fixing film 110 release heat.

In addition, do not have to be provided with and have the development length of the Width length that equals back edge 131R and from the rearwardly projecting nose section of back edge 131R, but be provided with along the spaced a plurality of outshots 132 of Width, be used for installing thermal resistor 170 thereon.Therefore, can reduce the volume or the thermal capacity of cramping plate 130.Correspondingly, can realize the Fast Heating of cramping plate 130, to quicken the startup timing of fixing device 100.

In addition, because between thermal resistor 170 and reflecting plate 140, limit the gap, so 170 heat transmission can be inhibited from Halogen lamp LED 120 to thermal resistor by reflecting plate 140.Correspondingly, thermal resistor 170 can accurately detect the temperature of cramping plate 130, improving temperature controlled accuracy, and saves the production cost of thermal resistor 170 because not needing the abundant thermal resistivity of thermal resistor.

Be used for installing of thermal resistor 170 because in pillar 160, form recess 161, so can provide the compactness of thermal resistor 170 to install and need not enlarge internal space S, specifically need not enlarge the gap between the inside surface of the outside surface of reflecting plate 140 and pillar 160 along the sheet feeding direction.Therefore, the heat at the internal space S place keeps and can be achieved.

In addition, be used for installing of thermal resistor 170 because in pillar 160, form recess 161, thus thermal resistor 170 can be positioned near the central part 131A of cramping plate 130, that is, and near the N of cramping zone.Correspondingly, can improve the response of thermal resistor 170, improve temperature controlled accuracy thus.

In addition, the situation along the outside of sheet feeding direction that is positioned at pillar 160 with thermal resistor is compared, and can reduce the size along the sheet feeding direction of cramping plate 130.Correspondingly, can reduce the thermal capacity of cramping plate 130, quicken thus with the startup of quickening fixing device 100 regularly for the heating of cramping plate 130.

Because thermal resistor 170 is configured to detect directly the temperature of the cramping plate 130 that is heated by Halogen lamp LED 120, so can utilize thermal resistor 170 accurately to detect the temperature of Halogen lamp LEDs 120 by cramping plate 130.Correspondingly, can improve temperature controlled accuracy.

Because thermostat 180 is oriented to the temperature of detection of reflected plate 140,, can realize the thermostat 180 layout degree of freedom that strengthen so compare with the situation that thermostat is oriented to detect the temperature of cramping plate 130.

In addition, between photographic fixing film 110 and thermostat 180 any sliding contact not taking place, avoids photographic fixing film 110 and thermostat 180 damage and wears thus.

In addition, because with respect to reflecting plate 140, thermostat 180 and Halogen lamp LED 120 relative positionings, thus for from Halogen lamp LED 120 towards the radiation heat of cramping plate 130 and reflecting plate 140 and at reflecting plate 140 for the cramping plate 130 radiation reflected heat, thermostat 180 does not become obstacle.Correspondingly, can realize with the startup of quickening fixing device 100 regularly for the Fast Heating of cramping plate 130.

In addition, suppose that thermostat and Halogen lamp LED are positioned at the place, the same side of reflecting plate, then need enough thermal resistivities in thermostat.Yet in the present invention, because with respect to reflecting plate 140, thermostat 180 and Halogen lamp LED 120 relative positionings be not so need improve thermal resistivity in thermostat 180.Correspondingly, can be with low-cost production thermostat 180.

Can imagine various modification.For example, in the fixing device 200 according to first modification shown in Figure 5, thermal resistor 170 is positioned at the upstream along the sheet feeding direction of reflecting plate 140.For reaching this purpose, pillar 260 has the antetheca 260F that is formed with recess 261, inserts thermal resistor 170 by recess 261.

For reaching this purpose, cramping plate 230 has the preceding elongated portion 231C that 231A from central division extends forward.Preceding elongated portion 231C can be used to preheat the part of photographic fixing film 110 as the preliminary heating section that contacts with the interior perimeter surface of photographic fixing film 110, and this part is right after the upstream of cramping zone N, improves the image fixing performance thus.

In addition, because thermal resistor 170 is installed on the upper surface of preceding elongated portion (preliminary heating section) 231C, so can utilize the inner space that in photographic fixing film 110, limits to install thermal resistor 170 efficiently.Just,, can reduce the space that in photographic fixing film 110, limits, reduce the girth of photographic fixing film 110 thus because do not need to be used to install the particular space of thermal resistor 170.Correspondingly, the circumference moving period that can reduce photographic fixing film 110 quickens the startup timing of fixing device 200 thus to suppress from photographic fixing film 110 release heat.

Fixing device 300 according to second distortion has been shown in Fig. 6 A, and its B-C post 360 is not formed with recess, but thermal resistor 170 is arranged at the outside of pillar 360 in pillar 360 location downstream.In addition, in the fixing device 400 according to the 3rd modification shown in Fig. 6 B, pillar 460 is not formed with recess, but thermal resistor 170 is arranged at the outside of pillar 460 in the position of pillar 460 upstreams.

Fixing device 500 according to the 4th modification shown in Figure 7 wherein is not provided with above-mentioned pillar.This reflecting plate 540 as an alternative, used reflecting plate 540, as long as can guarantee the rigidity of cramping plate 130 with enough rigidity.For example, reflecting plate 540 has the thickness greater than the embodiment of front.In other words, except its inborn reflex function, reflecting plate 540 also provides the function of pillar.As selection, can also need not pillar by the cramping plate that employing has enough rigidity.

In addition, according to the 4th modification, adopted to have the contact-type temperature sensor that uses among the embodiment that substitutes in front with the outshot 132 isolated non-contact type temperature sensors 570 that detect surface 571.Non-contact type temperature sensor 570 has the rib 573 that is fixed to reflection part 540 by screw 579.

In foregoing, thermal resistor 170 is as temperature sensor.Yet, can use thermostat or thermo-fuse place of thermistors device 170.In addition, the number that can change temperature sensor based on the size and the cost of fixing device.

In addition, can use infrared-ray well heater or carbon heater to substitute Halogen lamp LED 120.

In addition, in the above-described embodiments, be provided with single parts and form cramping plate 130.Yet, a plurality of parts can be set form cramping plate 130.

In addition, in the above-described embodiments, two outshots 132 are located at cramping plate 130 places, are used for installing two thermal resistors 170 thereon.Yet at least one among the 131B of end can be given prominence to forward or backward, is used for installing (one or more) thermal resistor thereon.In addition, can be provided with single or at least three outshots 132.

In the above-described embodiments, foundation 131 has outstanding downwards shape and makes central part 131A locate lowlyer than end 131B.Yet central part can be located De Genggao than the end.As selection, can also use smooth cramping plate.

In described embodiment, adopt pressure roll 150 as support unit.Yet, can also use banded press member.In addition, in described embodiment, utilize support unit (pressure roll 150) to contact cramping zone N is provided for the pressure of cramping parts 130.Yet, can also utilize the cramping parts to contact the cramping zone is provided for the pressure of support unit.

In the above-described embodiments, in pillar 160, form two recesses 161.Yet, can use through hole to substitute recess 161.

In addition, substitute common paper and postcard, sheet material P can be the OHP sheet material.

In addition, in described embodiment, imaging device is a monochromatic laser printer.Yet, can also use color laser printer, LED printer, duplicating machine and multi-function device.

Though describe the present invention in detail with reference to embodiment, it will be apparent to one skilled in the art that under the prerequisite that does not depart from spirit of the present invention, can make various changes and modification therein.

Claims

1. fixing device is used for the photographic fixing of developer thermal image to the sheet material along the feeding of sheet feeding direction, and described fixing device comprises:

The flexible fixing member of tubulose, the flexible fixing member of described tubulose has the interior perimeter surface that limits the inner space;

The cramping plate, described cramping plate is arranged in the described inner space, and has a surface and opposed surface, a described interior perimeter surface and a described surperficial sliding contact;

Well heater, described well heater is arranged in the described inner space, and faces described cramping plate along faces direction:

Reflecting plate, described reflecting plate from described well heater towards described cramping plate reflected radiation heat;

Support unit, described support unit match with described cramping plate the cramping zone are provided, and are used for the flexible fixing member of the described tubulose of cramping between described support unit and described cramping plate; With

Temperature sensor, described temperature sensor is arranged in the described inner space, and detects the temperature of described cramping plate, described temperature sensor be positioned at described reflecting plate along the outside of described sheet feeding direction and in the face of described opposed surface.

2. according to the fixing device of claim 1, the flexible fixing member of wherein said tubulose is the photographic fixing film.

3. according to the fixing device of claim 2, wherein said temperature sensor directly contacts with described opposed surface.

4. according to the fixing device of claim 2, wherein said temperature sensor and described opposed surface be restriceted envelope between described temperature sensor and described opposed surface.

5. according to the fixing device of claim 2, wherein said temperature sensor is positioned at the outside along described sheet feeding direction in described cramping zone.

6. according to the fixing device of claim 2, wherein said temperature sensor is positioned at the downstream along described sheet feeding direction of described reflecting plate.

7. according to the fixing device of claim 2, wherein said temperature sensor is positioned at the upstream along described sheet feeding direction of described reflecting plate.

8. according to the fixing device of claim 2, wherein said cramping plate has along the outstanding outshot of described sheet feeding direction, and described temperature sensor is in the face of described outshot location.

9. according to the fixing device of claim 2, wherein said cramping plate have along with the outstanding in the opposite direction outshot in described sheet feeding side, described temperature sensor is in the face of described outshot location.

10. according to the fixing device of claim 2, wherein said temperature sensor and described reflecting plate limit the gap between described temperature sensor and described reflecting plate.

11. the fixing device according to claim 2 further comprises:

Pillar, described pillar covers described reflecting plate and supports described cramping plate, described pillar has the profile that conforms to the exterior contour of described reflecting plate, and described pillar is formed with one in through hole and the recess, and described temperature sensor extends through described in described through hole and the recess.